describe 3 ways in which your immune system defends the body against diesis

skin, mucus and hair

4 of 50

describe how the MMR vaccine prevents you getting measles, mumps and rubella

the vaccine contains dead or inactive versions of the measels, mumps and rubella microorganisms. These carry antigens. So white blood cells create antibodies for those specific microorganisms that destroy them.

5 of 50

why shouldn't your doctor give you antibiotics for the flu?

because you can easily become resistant to it. As becateria mutate and the mutations cause them to become resistant to (not killed by ) an antibiotic.

6 of 50

Name one type of bacteria that has developed resistance to antibiotics

MRSA

7 of 50

What practise did Semmelweis introduce in 1840s ? why did this reduce death rates on his ward?

telling doctors entering his ward to wash their hands in an antiseptic solution he cut the date rate from 12% to 2% because the bacteria was killed and not spread to the patients.

8 of 50

describe the structure of the central nervous system and explain what it does.

The CNS consists of the brain and the spinal cord and it is where all the information from the sense organs is sent and where the reflexes and actions are coordinated.

9 of 50

where do you find the smell and taste receptors?

smell receptors are found in the nose and taste receptors are found in the tongue.

A nerve is a fast action , it acts for a very short time. It acts on a very precise area. Hormones are slower actions, they act for a long time and act in a more general way.

15 of 50

describe briefly the menstrual cycle

Day one is when the bleeding starts because the uterus lining breaks down for 4 days. The lining build up again from day 4-14. An egg is realised from the ovary at day 14 and the wall is then maintained for about 14 days untill day 28.

16 of 50

describe two effects of FSH on the body

produced by the pituitary gland. Causes an egg to mature in one of the ovaries and stimulates the ovaries to produce oestrogen.

17 of 50

Describe two effects of oestrogen

produced by the ovaries and causes pituitary gland to produce LH and inhibits the further release of FSH.

18 of 50

Describe 2 effects of LH on the body

produced by the pituitary gland and stimulates the release of an egg at around the middle of the menstrual cycle.

19 of 50

state 2 disadvantages and advantages of using the contraceptive pill.

over 99 % effective at preventing pregnancy and it reduces the risk of getting some types of cancer. But not 100% effective, caused side effects such as headaches, nausea and irregular menstrual bleeding and also it doesnt protect against STDs

20 of 50

What is Auxin? Explain how Auxin causes plant shoots to grow towards light,

Auxin is a plant hormone. It controls growth near the tips of shoots and roots in response to light. (phototropism)

21 of 50

describe briefly how IVF is carried out.

egg is collected from womens ovaries and fertilised in a lab using a mans sperm. These are then grown into embryos . Once the embroys are tiny balls of cells one or two of them are then transferred to the womens uterus (womb)

22 of 50

Why is FSH and LH given before egg collection in IVF?

To stimulate egg production.

23 of 50

descibe how the amount and concentration of water content varies based on how hot it is and how much exercise is done.

if its hotter more water content will be lost as sweat and urine will be a lot more concentrated.

24 of 50

why might an athlete use performing-enhancing drugs like steroids and why might they not use them?

they may use them because some increase muscle size and also increase heart rate, but some may not because they may believe it is unfair and negative health effects such as high blood pressure.

25 of 50

briefly describe how a double blind drug trial works.

two groups one has the real the drug while the other group has the 'placebo' drug which is a fake version of the drug. So the doctor can see the actual difference the drug is making.

26 of 50

Name a drug that was not tested thoroughly enough and the consequences of its use.

Thalimode was originally a sleeping pill but was then used for morning sickness for pregnant women. The drug was not tested throughly and caused abnormal limb development.

27 of 50

Describe 2 opinions about the the link between cannabis and hard drug use.

cannabis is a stepping stone to harder drugs. Cannabis use brings people into contact with drug dealers.

28 of 50

which has the biggest impact on society in the uk, legal or illegal drugs?

legal, because things like smoking and alcohol cause heart disease and lung disease as well as causing cancer.

29 of 50

Name 4 ways in which a desert animal may be adapted to its environment

large surface area to volume (lose more body heat), produces small amounts of concentrated urine, thin layers of body fat to lose heat, sandy colour to camouflage.

30 of 50

State 3 ways that plants and animals might deter to predators.

armour like thorns or sharp spines, others produce poisons like bees and some have warning colours to scare off predators.

31 of 50

Name 3 things plants compete for and 3 things animals compete for

plants compete for sunlight, water and space while animals compete for food , water and mates.

32 of 50

Give two examples of non-living factors that can cause environmental changes

a change in temperature and a change in average rainfall.

33 of 50

Explain how lichen can be used as an indicator of air pollution

Lichen are very sensitive to the concentration of sulfur dioxide so if there are many it means its cleaner as less sulfur dioxide is present.

34 of 50

Name one organism that can be used as indicator of water pollution.

mayfly larvae.

35 of 50

what does each bar on a pyramid of biomass represent?

each bar shows the mass of living material at that stage of the food chain.

36 of 50

Give two ways that energy is lost from a food chain?

heat and movement.

37 of 50

Give one way that carbon dioxide from the air enters a food chain

plants take co2 in from photosynthesis and animals eat them.

38 of 50

Give three ways that carbon compounds in a food chain become co2 in the air again.

animal respiring, plant respiring and co2 realised from decay.

39 of 50

Name 3 animal characteristics that are determined only by genes

eye colour, hair colour, blood group.

40 of 50

Name 3 animal characteristics that are determined by a mixture of genes and the environment.

height, weight, skin colour

41 of 50

How many pairs of chromosomes do humans have in each cell

23

42 of 50

explain sexual reproduction

sexual reproduction involves the fusion of male and female gametes. Because there are two parents, the offspring contain a mixture of thier parents genes.

43 of 50

explain asexual reproduction

A sexual only has one parent. Theres no fusion of gametes, no mixing of chromosomes and no genetic variation between parent and offspring.

44 of 50

how would you make a plant clone using tissue culture?

A few plant cells are put in a growth medium with hormones, and they grow into new plant clones of the parent plant.

45 of 50

State two examples of applications of genetic engineering

to produce human insulin and GM crops.

46 of 50

why are some people concerned about genetic engineering?

because not all of its long term effects are fully understood.

47 of 50

Explain Darwins theory of natural selection

individuals characteristics make them better adapted to the environment so better chance of survival. Therefore are more able to breed successfully.

48 of 50

why was Darwins theory of natrual selection very controversial at the time?

it went against religious beliefs about how life on earth was formed.

49 of 50

How was Lamarcks theory different from Darwins theory?

Lamarck argued that if a characteristic was used a lot by an orgainism then it would become more developed. Lamarck believed that these acquired characteristics would be passed on to the next generation.